There were 4,119 households out of which 35.3% had children under the age of 18 living with them, 52.1% were married couples living together, 15.7% had a female householder with no husband present, and 27.1% were non-families. 21.7% of all households were made up of individuals and 9.8% had someone living alone who was 65 years of age or older. The average household size was 2.63 and the average family size was 3.02.

In the city the population was spread out with 27.2% under the age of 18, 9.0% from 18 to 24, 27.8% from 25 to 44, 20.8% from 45 to 64, and 15.3% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 92.2 males. For every 100 females age 18 and over, there were 89.6 males.

The median income for a household in the city was $34,184, and the median income for a family was $36,303. Males had a median income of $30,468 versus $21,232 for females. The per capita income for the city was $15,510. About 13.4% of families and 17.3% of the population were below the poverty line, including 28.3% of those under age 18 and 7.6% of those age 65 or over.

In 2010 Auburndale had a population of 13,507. There were 4,933 households with 99.1% of the population living in households. The racial and ethnic composition of the population was 71.7% non-Hispaic white, 12.8% black or African American, 0.4% Native American, 0.4% Asian Indian, 0.2% Chinese, 0.1% Japanaese, 0.1% Korean, 0.1% Vietnamese, 0.1% other Asian, 0.1% non-Hispanic reporting some other race, 2.2% from two or more races and 13.1% Hispanic or Latino. The largest number of Hispanics, at 7.1% were Mexicans, with 3.2% of the population being Puerto Ricans, 0.7% being Cubans and the remaining 2.1% being classified as "other Hispanic".[11]

The public schools in Auburndale are operated by the Polk County School Board. There are five elementary schools, Berkley Elementary(a charter school ), Auburndale Central Elementary, Lena Vista Elementary, Boswell Elementary and Caldwell Elementary in Auburndale which feed into Stambaugh Middle School, though students from Berkley Elementary are admitted into Berkley Accelerated Middle School(another charter school), while other students wishing to apply are put on a waiting list. Auburndale High School is the only high school in Auburndale, although nearby Tenoroc High School serves students in both Auburndale and Lakeland.